The present invention relates to room air conditioners and is more specifically directed to the configuration of a condensate suction port provided in a condenser coil fan orifice member to facilitate delivery of condensate to a condenser fan having a condensate slinger.
In air conditioning systems, condensation normally collects on the evaporator coil, runs off and must be disposed off. In small packaged air conditioning units, such as room air conditioners or what are known as xe2x80x9cpackaged terminal air conditionersxe2x80x9d (PTAC), it is common to direct the condensate through various passageways to the outdoor section of the air conditioner where the compressor, condenser coil and condenser fan are located. When the air conditioner has been in operation for some time, a pool of condensate will collect in the outdoor section of the basepan. Several ways are known for dealing with the collected condensate in order to improve condenser capacity and the energy efficiency rating (EER) of the air conditioning unit. One of these is provide a slinger arrangement associated with the condenser fan. In a typical slinger arrangement, a blow through propeller fan coil configuration is used and the condensate collects at a location where the fan structure causes the condensate to be splashed onto the condenser coil where it is evaporated, thereby providing cooling to the condenser.
U.S. Pat. No. 6,067,812, assigned to the assignee of the present invention, entitled xe2x80x9cCondenser Fan With Condensate Slingerxe2x80x9d, describes a system having an axial condenser fan which has an annular slinger surrounding and having a portion secured to the blade tips of the condenser fan in a region extending from the suction side of the fan for at least a portion of the distance to the discharge side. A fixed shroud having an inlet orifice surrounds the fan and the slinger with the tips and the slinger being located entirely within the fixed shroud. The inlet orifice of the fixed shroud and the slinger coact to define a restricted passage extending between the suction side and the discharge side of the fan. The slinger includes means for contacting condensate collecting thereunder and being wetted thereby such that the collected condensate tends to adhere to the slinger. As a result, when the unit is operating and the fan and slinger rotate as a unit, a pressure differential across the fan acts on the collected condensate tending to cause the collected condensate to move towards and to be at a higher level towards the suction side and the slinger contacts the higher level of collected condensate and is wetted. Condensate adhering to the slinger is then slung by centrifugal force into air discharging from the fan blades.
With the above described system, an opening is provided in the fixed shroud underlying the fan inlet orifice to provide a path for condensate to pass into the region underlying the fan and slinger. It has been found that under some operating circumstances, condensate may not pass freely through such orifice and, accordingly, the slinger system is not allowed to operate as efficiently as contemplated.
The present invention relates to an orifice member for the condenser fan of an air conditioning unit, which has a basepan and a partition which divides the air conditioning unit into an indoor section forwardly of the partition and an outdoor section rearwardly of the partition. The indoor section includes an evaporator coil, an evaporator fan and means for collecting condensate and directing the condensate to the basepan in the outdoor section. The outdoor section includes a condenser coil at the rear thereof, a rotatably driven condenser fan having a second side and a discharge side, the fan being located forwardly of the condenser coil. The orifice member defines a barrier between the suction and discharge side of the condenser fan and has a fan orifice opening forwardly of the fan to define a restricted air flow passage therethrough between the suction side at a generally low pressure and the discharge side at a generally high pressure. The condenser fan is an axial fan with blades having tips extending from the suction side to the discharge side. The fan includes an annular slinger surrounding and having a portion secured to the blade tips in the region extending from the suction side to the discharge side. The tips and the slinger are located entirely rearwardly of the orifice member. The fan orifice and the slinger cooperate to define a first narrow annular passage therebetween. The slinger defines a second narrow annular passage with the underlying portion of the basepan, which is configured to collect condensate therein. The orifice member has a wall section underlying the fan orifice opening. The fan orifice opening has an imaginary vertically extending centerline and the wall section has an opening therein centered upon the centerline, which fluidly communicates the region of the basepan forwardly of the wall with both the first and second annular passages. The fluid opening has a narrow lateral dimension at the lower end thereof and a larger lateral dimension at the upper end thereof.